[FIX] base: allow to remove fields when the registry is not ready

When the registry is not ready, allow modifications of the selections

The following use case must reset the values:
- removing a selection on a custom field via studio
- changing the static selection definition and updating the module

The value must NOT be reset when:
- trying to remove manually a base field
- updating a module without all override being computed yet
(i.e. install)

Fully replacing the selections in an override should not happen

Instead of relying on the context, check if the registry is ready
before marking the selections as to remove.
If a static selection is removed and the module updated, it will be
removed correctly during the _process_end method as the selections
will not be present in pool.loaded_xmlids

Before this commit, updating a module A was doing a SET NULL for
selection values added by a module B via a selection_add

closes odoo/odoo#35871

Signed-off-by: Raphael Collet (rco) <rco@openerp.com>


Co-authored-by: Martin Trigaux <mat@odoo.com>

odoo/addons/base/models/ir_model.py

@@ -1042,11 +1042,11 @@ class IrModelSelection(models.Model):
         for value in new_rows.keys() | cur_rows.keys():
             new_row, cur_row = new_rows.get(value), cur_rows.get(value)
             if new_row is None:
-                if not self._context.get(MODULE_UNINSTALL_FLAG) and not self._context.get('module'):
+                if self.pool.ready:
                     # removing a selection in the new list, at your own risks
                     _logger.warning("Removing selection value %s on %s.%s",
                                     cur_row['value'], model_name, field_name)
-                rows_to_remove.append(cur_row['id'])
+                    rows_to_remove.append(cur_row['id'])
             elif cur_row is None:
                 rows_to_insert.append(dict(new_row, field_id=field_id))
             elif any(new_row[key] != cur_row[key] for key in new_row):
@@ -1125,7 +1125,7 @@ class IrModelSelection(models.Model):
     def unlink(self):
         # Prevent manual deletion of module columns
         if (
-            not self._context.get(MODULE_UNINSTALL_FLAG) and not self._context.get('module')
+            self.pool.ready
             and any(selection.field_id.state != 'manual' for selection in self)
         ):
             raise UserError(_('Properties of base fields cannot be altered in this manner! '